Testing & validation
FAT / SAT
Prove the system works before it ships (FAT) and once it is installed (SAT) — with every safety function tested and signed off.
Factory and Site Acceptance Testing
- Category
- Testing & validation
- Scope
- Industry practice
- Edition / refs
- IEC 62381 · IEC 61511 · project specifications
MSA output
- Safety matrix (FAT/SAT)
- Device test records & fault injection tests
- NCR register
- Test certificates & sign-off documentation
- Document extraction engine
What is FAT / SAT?
A Factory Acceptance Test (FAT) verifies equipment or a control system at the supplier’s premises, before shipment, against the agreed specification. A Site Acceptance Test (SAT) repeats or completes that verification after installation, connected to real utilities, field devices and interfaces.
For safety-related systems, FAT and SAT are where safety functions are first proven end to end: each function is exercised, faults are injected and the response is recorded. IEC 62381 provides a framework for FAT, SAT and integration tests in process automation, and IEC 61511 treats FAT and SIS safety validation as defined life-cycle activities.
Who it applies to
- System integrators delivering cells, lines and control systems
- Machine builders and OEMs
- Commissioning engineers
- End users and their representatives witnessing tests
Key requirements
- 01
Agreed test plan
Test procedures agreed with the customer and referenced to the specification.
- 02
Safety matrix
Each safety function or cause-and-effect line mapped to test steps and expected results.
- 03
Device and I/O checks
Verify each device, its wiring, addressing and configuration.
- 04
Fault injection
Confirm the safe state on faults such as wire break, sensor discrepancy and loss of power or communication.
- 05
Non-conformances
Record, classify and close out every NCR before acceptance.
- 06
Certificates and sign-off
Issue test certificates and capture witness and customer signatures.
Summary for orientation only. Always refer to the current official text of FAT / SAT and any applicable legislation.
MSA for FAT / SAT
What MSA generates
Evidence produced from your engineering inputs, traceable end to end and exported to Word, PDF or Excel.
Safety matrix (FAT/SAT)
Generated from the safety functions defined upstream, so nothing is missed.
Device test records & fault injection tests
Per-device and per-fault procedures with recorded results.
NCR register
Non-conformances tracked from discovery to close-out.
Test certificates & sign-off documentation
Client-ready certificates and approvals, exported to Word, PDF or Excel.
Document extraction engine
Pulls data from existing engineering documents to build test packs.
Frequently asked questions
What is the difference between FAT and SAT?
FAT happens at the supplier’s facility before shipment, often with simulated I/O. SAT happens on site after installation, with real field devices, utilities and interfaces.
Is a FAT mandatory?
Usually it is a contractual requirement rather than a legal one. IEC 61511 expects the need for a FAT to be decided during design, while SIS safety validation on site is required before the hazards are introduced.
What is a safety matrix?
A table that maps each safety function — or each cause in a cause-and-effect chart — to its expected effects and the test steps that prove them, with results and signatures.
Generate FAT / SAT evidence from your own data
See how MSA turns your requirements, drawings and process data into certification-ready documents — fully offline.